2D Tellurium Films Based Self-Drive Near Infrared Photodetector

To reduce the amount of energy consumed in integrated circuits, high efficiency with the lowest energy is always expected. Self-drive device is one of the options in the pursuit of low power nanodevices. It is a typical strategy to form an internal electric field by constructing a heterojunction in self-drive semiconductor system. Here, a two-step method is proposed to prepare high quality centimeter-sized 2D tellurium (Te) thin film with hall mobility as high as 37.3 cm² V^-1 s^-1, and the 2D Te film is further assembled with silicon to form a heterojunction for self-drive photodetector, which can realize effective detection from visible to near infrared bands. The photodetectivity of the heterojunctions can reach 1.58×10¹¹ Jones under the illumination of 400 nm@ 1.615 mW/cm² and 2.08×10⁸ Jones under the illumination of 1550 nm@ 1.511 mW/cm² without bias. Our experiments demonstrate the potential of 2D tellurium thin films for wide band and near infrared integrated device applications.